Global warming is a key subject that many educators and scientists say should be, but isn't, taught in every school. And as with other emerging sciences, there remains a need, they say, for more materials available for teachers to incorporate into their lessons.

"It's not a formalized part of the curriculum," said John Rudolph, associate professor in the Department of Instruction and Curriculum at the University of Wisconsin at Madison. "It is more of an individual teacher's initiative."

But when Laurie David, the producer of the global warming documentary "An Inconvenient Truth," narrated by former vice president Al Gore, wanted to distribute 50,000 copies to schools across the country, the National Science Teachers Association said it wouldn't help her.

Energy conglomerates pay big bucks to have their propaganda taught in your schools.